You know, just because a person becomes a vampire's familiar doesn't mean they have to be automatically be treated like crap.
I mean, just look at Fright Night. Billy Cole is a perfect example of a well taken care of and well-loved familiar that has been serving his vampire for a very long time. He obviously gets plenty of food, sleep, and affection.
He doesn't even need to be ordered to do things, he bounces to the task on his own. His vampire's even appreciative.
On the other hand, look at this disheveled little rat (affectionate).
I don't think there's ever been a version of Renfield that didn't look like a wet mop had suffered a complete mind break. Just look at this damaged critter...
It didn't need to be this way.
Dracula's just a selfish, abusive ass.